Annealing leer



May 1, 1934.

R. P. CALLARD y ANNEALING LEER Filed Sept. 14, 1951 2 Sheets-Sheet l lwentor @am P ca//mfg vcyuwme l gl May l, l934- R. P. cALLARD 1,957,132

ANNEALING LEER Filed'sept. 14,1931 2 sheets-sheet 2 @"@jjrl T :L 1:: .5 :inventor Poberz @Cal/0rd.

Patented May il, 1934 vnutren STATES PATENT OFFICE ANNEALING LEER Application September 14, 1931, Serial No. 562,793

11 Claims.

The present invention relates broadly to improvements in annealing leers or ovens, and more particularly to a leer for use in the annealing of sheet glass.

An important object of this invention resides in the provision of ay novel leer of the so-called tunnel type wherein it is possible to maintain a more even and uniform temperature in surrounding relation to the glass sheet as it is caused,

to travel therethrough to the endthat a better annealing action may be achieved.

Another important object of the invention is the provision of an annealing leer of the character above described, so constructed as to require the use of less fuel in the heating thereof, whereby a conservation of gas may be effected with a corresponding reduction in operating costs.

Other objects and advantages of the invention will become more apparent during the course of the following description when taken in connection with the accompanying drawings. I

In the drawings forming a part of this application and wherein like numerals are employed to designate like parts throughout the same,

Fig. 1 is a vertical'longitudinal section through an annealing leer constructed in accordance with the present invention,

Fig. 2 is a transverse section therethrough, and Fig. 3 is a side elevation of a portion of the leer.

Referring now to the drawings, the annealing leer 5 herein provided is of the so-called continuous tunnel type and comprises a bottom 6, opposite side walls 'l and 8, and a top 9, the said bottom, side and top walls being preferably constructed of a suitable insulating material. Arranged within the leer and disposed transversely thereof are a series of horizontally aligned rolls 10 which serve to support and advance the glass sheet 11 to be annealed therethrough. The leer rolls 10 are rotatably mounted at their opposite ends in the side walls 7 and 8 of the leer and are adapted to -be positively driven in any wellknown or preferred manner. As the glass sheet 11 travels through the leer, it is gradually cooled and, at the same time, internal stresses. and strains are removed therefrom, so that when the said sheet leaves the leer it is properly annealed. Positioned within the leer above the path of travel of the glass sheet 11 are a`. plurality of heat-retaining members 12 in the form of flat rectangulanplates, which plates are preferably, though not necessarily, disposed in substantial horizontal alignment with one another-during the normal operation of the leer. Each plate 12 is suspended adjacent its opposite ends and at each side thereof by hanger rods 13 and la pivotally connected to said plate as at 15 and 16 respectively. The hanger rods 13 and 14e at each side of the plate are also pivotally connected at their upper ends by means of the links 17 and 18 to the legs 19 and 20 of the bell-crank levers 21 and 22 respectively.` The opposed bell-crank levers 21 and 22 at opposite sides of the plate 12 are mounted upon and connected by cross shafts 23 and 24 carried by supporting brackets 25 and 26 respectively, while the two bell-crank levers at each side of the plate are tied together by a tie-rody 27 extending between and secured to the legs 28 and 29 of the said bell-crank levers 21 and 22. With thisy construction, it will be readily apparent that the bell-crank levers 21 and 22 will be caused to operate in unison so as to effect a raising or lowering of the respective plate 12 while maintaining it in a horizontal position. The bell-crank levers 22 may have formed thereon extensions 30 carrying the counter-weights 31 which serve to counter-bal'.- ance the corresponding plate 12.

There is also carried by each shaft 24 at one end thereof an operating lever 32 provided adjacent its lower end with a vertically elongated slot 33 through which is received the rod 34 extending longitudinally of the leer, and this rod of course passes through the slots 33 in the several operating levers l32. Mounted upon the rod 34 are a plurality of collars 35, one being provided for each operating lever and being secured to the rod when desired by means of a. set screw or the like 36. When these collars 35 are properly positioned uponthe rod 34 and secured thereto, sliding movement of the said rod to the right in Fig. 3 will tend to swing all of the levers 32 to the right, thereby causing a rocking of the bell-crank levers 21` and 22 to effect simultaneous raising of all of the heat-retaining plates 12. Howeven the collars can be so placed upon` the rod that upon movement of said rod, certain of the plates 12` will not be raised at all, while the remaining plates will be raised varying degrees. Should it be dey sired to raise any one heat-retaining plate such as when it becomes necessary to cut the sheet, it is simply necessary for the operator to grasp the handle 37 at the lower end of the desired lever 32 and swing it to the right.

Positioned beneath the leer rolls 10 are a plurality of additional heat-retaining members 38 also preferably in the form of nat rectangular plates, each being hinged `at one end upon a transverse shaft 39. Under normal operating conditions, the plates 38 are likewise disposed in horizontal alignment with one anotherso that they cooperate with the upper plates 12 and the side walls 7 and 8 of the leer to substantially enclose the sheet. On the other hand, upon breakage of the sheet, one or more of the lower heatretaining plates 38 may be swung dc-wnwardlyto permit the discharge of the broken glass or cullet through the openings 40 in the leer bottom, after which the plate or plates may be again raised to a horizontal position. One of the openings 40 is provided for each plate 38 and is normally closed by a door 41 hinged as at 42. A guide 43 is provided at the side of each opening 40 opposite the corresponding plate 38 to direct the broken glass downwardly through the respective opening. In order to facilitate the swinging movement of the heat-retaining plates 38, each shaft 39 extends at one end beyond the side of the leer and has keyed thereto a worm gear 44 meshing with a worm 45 mountedn upon shaft 46 having a hand-wheel 47. Upon rotation of the hand-wheel 47, it will be readily apparent that the corresponding plate 38 may be raised or lowered as desired.

Positioned within the leer beneath certain of the rolls 10 but above the heat-retaining plates 38 are a plurality of gas burners 48, these burners being spaced longitudinally of the leer and extending transversely thereof. Each gas burner may consist of an ordinary Vpipe having a large number of openings or apertures 49 therein, and these openings are so positioned that the heating flame is directed horizontally into the leer. Disposed directly above the burners 48 are iiame guards 50.

With a .leer of the type described above, the upper and lower heat-retaining plates 12 and 38 cooperate with the side walls of the leer to substantially enclose the sheet or, in other words, to form a substantially closed chamber of relatively small cross sectional area, through which the sheet is passed. The upper'and lower plates 12 and 38 serve to retain the major portion of the heat within this confined area or chamber, as a result of which a more even and uniform temperature may be maintained in surrounding relation to the sheet, to the end that a. better annealing action may be had. The provision of the dead air spaces above and beneath' the plates 12 and 38 also facilitates the maintaining of a uniform temperature condition around the sheet.

It is to be understood that the form of the invention herewith shown and described is to be taken as the preferred embodiment of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, and horizontally disposed heat-retaining means also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation to the top and bottom of said leer, said heating means being located be- `tween said heat-retaining means.

2. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting' and advancing the sheet therethrough, means for heating-.the leer, horizontally disposed heat-retaining members also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation to the top and bottom of said leer, said heating means being located between the heat-retaining members, and means for adjustably mounting certain of said heat-retaining members.

3. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, and heat-retaining members also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation to the top and bottom of said leer, said members cooperating with the side Walls of the leer to substantielly enclose the sheet, said heating means being located between the upper and lower heatretaining members.

4. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, horizontally disposed heat-retaining members also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation to the top and bottom of said leer, said heating means being located between the upper and lower heat-retaining members, and

means for adjusting certain of said 'neat-retaining members vertically, the heat-retaining members cooperating with the side walls of the leer to substantially enclose the sheet;

5. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, horizontally disposed heat-retaining members also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation lto the top and bottom of said leer, 'said heating means being located between the upper and lower heat-retaining members, and means for hingedly mounting certain of said heat-retaining members, the heat-retaining members cooperating with the side walls of the leer to'substantially enclose the sheet.

6. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, horizontally disposed heat-retaining members also positioned within the leer above and beneath the path of travel of the sheet and in spaced relation to the top and bottom of said leer, said heating means being located between the upperl and lower heat-retaining members, means for adjusting certain of the heat-retaining members vertically, and means for hingedly mounting other of said heat-retaining members, the heat-retaining members cooperating with the side walls of the leer to substantialy enclose the sheet.

7. In a sheet glass annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, a series of heat-retaining plates positioned above the path of travel of the sheet, a second series of heat-retaining plates positioned beneath the path of travel of the sheet and cooperating with the upper plates and the side walls of the leer to substantially enclose the sheet, said heating means being located between said upper and lower heat-retaining plates, means for raising and lowering the upper plates independently of notarse one another, and means or moving all of said upper plates simultaneously.

8. En a sheet glass annealing leer of the tunnel type including a-bottom, side walls and a top, means Within the leer for supporting and advancing the sheet therethrough, means for heating the leer, a series of heat-retaining plates positioned above the path of travel of the sheet, a second series of heat-retaining plates positioned beneath the path of travel of the sheet and cooperating with the upper plates and the side walls of the leer to substantially enclose the sheet, means for hingedly mounting said lower platesf and means for moving each lower plate about its pivot to bring the same either into a horizontal@ position or an inclined position.

9. ln a. sheet glass annealing leer of the tunnel type including a bottom, side walls and a top,- means within the leer for supporting and advancing the sheet therethrough, means for heating the leer, a series of heat-retaining plates positioned above the path of travel of the sheet, a second series of heat-retainingf plates positioned beneath the path of travel of the sheet and cooperating with the upper plates and the side walls of the leer to substantially enclose the sheet, means for raising and lowering the upper plates independently of one another, means for moving all of said upper plates simultaneously, means for hingedly mounting said lower plates, and means for moving each lower plate about its pivot to bring the same either into a horizontal position or an inclined position.A

l0. in an annealing leer of the tunnel type including a bottom, side Walls and a top, means within the leer for supporting and advancing the work therethrough, heat-retaining means positioned within the leer above and beneath the path of travel of the Work and in spaced relation to the top and bottom of said leer, said last mentioned means cooperating with the side walls of the leer to form a. substantially closed chamber of relatively smaller cross sectional area than that of theleer, and heating means located within said chamber.

11. In an annealing leer of the tunnel type including a bottom, side walls and a top, means within the leer for supporting and advancing the work therethrough, horizontally disposed heatretaining members positioned Within the leer in end to end relation above and beneath the path of travel of the work and in spaced relation to the top and bottom of said leer, said members cooperating with the side walls of the leer to form a substantially closed chamber o! relatively smaller cross sectional area than that of the leer, and heating means located within said chamber.

ROBERT P. CALLARD. 

